Airplane wing profiles can be cited for which the drag and lift has to be evaluated.
Methods for calculating in two dimensions by singular points or analytically are known.
Three-dimensional simulations by finite elements are also known.
One of the difficulties in fluid mechanics is acquiring the value of the physical quantity of the flow in a three-dimensional space.
Another difficulty is modeling, in fluid mechanics, complex profiles or objects in three dimensions.
In effect, having to measure a physical quantity of a fluid flow in three dimensions considerably weighs on the calculation times.
From the following documents, cases of applying the DPSM method are known for calculating the propagation of a wave in a space containing a fluid and a solid, by means of the distributed source calculation:
“Wave propagation in a fluid wedge over a solid half-space—Mesh-free analysis with experimental verification”; Cac Minh Dao, Samik Das, Sourav Banerjee, Tribikram Kundu; International Journal of Solids and Structures, New-York, US; vol. 46, no 11-12, 1st Jun. 2009, pages 2486-2492 (D1),
“Mesh-free distributed point source method for modeling viscous fluid motion between disks vibrating at ultrasonic frequency”; Yuji Wada, Tribikram Kundu, Kentaro Nakamura; The Journal of the Acoustical Society of America, American Institute of Physics for the Acoustical Society of America, New York, US; vol. 136, no 2, August 2014, pages 466-474 (D2),
“Ultrasonic field modeling by distributed point source method for different transducer boundary conditions”; Tamaki Yanagita, Tribikram Kundu, Dominique Placko; The Journal of the Acoustical Society of America; vol. 126, no 5, November 2009, page 2331 (D3),
“Ultrasonic field modeling in plates immersed in fluid”; Sourav Banerjee, Tribikram Kundu; International Journal of Solids and Structures, New York, US; vol. 44, no 18-19, 2007, pages 6013-6029 (D4),
“Ultrasonic field modeling: a comparison of analytical, semi-analytical, and numerical techniques”; Tribikram Kundu, Dominique Placko, Ehsan Kabiri Rahani, Tamaki Yanagita, Cac Minh Dao; IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, IEEE, US; vol. 57, no 12, December 2010, pages 2795-2807 (D5),
“Ultrasonic field modeling in multilayered fluid structures using the distributed point source method technique”; Sourav Banerjee, Tribikram Kundu, Dominique Placko; vol. 73, no 4, July 2006, pages 598-609 (D6),
WO 2011/092210 A1 (D7),
FR 2 895 544 A1 (D8),
“Ultrasonic Field Modeling of Transient Wave Propagation in Homogenous and Non-Homogenous Fluid Media Using Distributed Point Source Method (DPSM)”; Raghu Ram Tirukkavalluri, Dr. Abhijit Mukherjee, Sandeep Sharma; Internet Citation, 2008, pages 1-113 (D9).
However, the sources calculated in these documents do not make it possible to correctly model a fluid flow. In effect, in fluid mechanics, the equations are nonlinear, notably because of the fluid convection term not being involved in the modeling of waves. On the contrary, for the propagation of the waves, the equations have been linearized about a point of operation. Also, an ultrasound wave being propagating in a fluid according to the state of the art cannot be likened to a fluid flow. The propagation of an ultrasound wave in a fluid involves only a small oscillatory or alternating movement of fluid particles about a position of equilibrium, that is to say that some fluid particles which are the vehicle of the propagation of the ultrasound wave step by step each move by a small length and return to their position of equilibrium repetitively. The propagation of an ultrasound wave in a fluid therefore comes under a microscopic alternating movement of certain fluid particles, and not of a microscopic movement of all the fluid for a fluid flow.
Thus, for example in the case where the fluid is air, the documents D1 to D9 do not make it possible to take account of vortexes in proximity to an airplane wing.
The invention aims to take account of the convection or turbulence terms, specific to a fluid flow arriving in the vicinity of an interface.
The aim of the invention is to obtain a device and a method which make it possible to measure at least one physical quantity of at least one fluid flow in a three-dimensional space, which mitigate the drawbacks of the prior art, by being reliable, rapid and directly applicable to fluid mechanics.